Design a Social Media Feed

Build a news feed system similar to Twitter or Instagram that aggregates and ranks content from followed users.

Functional Requirements

• Display posts from followed users in a personalized feed
• Support likes, comments, and shares
• Real-time updates when new posts are created
• Content ranking based on relevance and engagement
• Support for different content types (text, images, videos)

Non-Functional Requirements

• Feed generation under 100ms
• Support users following thousands of accounts
• Handle viral posts with millions of interactions
• Consistent experience across devices

Questions to Consider

• Will you use push (fanout-on-write) or pull (fanout-on-read)?
• How do you rank posts for relevance?
• How do you handle celebrity accounts with millions of followers?